Coating composition



. Patented ,llurne 30, 1931 :e'; earrca FREDERICK C. HAHN, OF WILIHNGTON, DELAWARE, ASSIGNOR TO E. I. DU FONT DE NEMOURS 6 a COMPANY, OF.WILMINGTON, DELAWARE, A CORPORATION OF DELA- WARE No Drawing.

This invention relates to the art of coating compositions, and more particularly to coat ing compositions containing cellulose acetate.

The quick-drying coating-compositions, often referred to as lacquers, now on the market ,are made out of cellulose nitrate,

one or more resins, one or more softeners and a solvent. For various reasons,it is desirable to use cellulose acetate as the base for such coating compositions but I have found that none of the ordinary natural resins are compatible with cellulose acetate, hence it is not possible to make these compositions by merely substitutingcellulose acetate for cel- 'lulose nitrate.

I- have found, however, that resin-like materials which are readily'miscible with cellulose acetate can be prepared by treating a d monoalkyl; ether of 'glycerine with organic acids containing two or morecarboxyl groups. It is therefore an object of this invention to produce coating compositions using cellulose acetate as the base. I 25 With the above and other objects in view, which will be apparent as the description proceeds, I have set forth below several embodiments of my invention by way of illustration and not as a limitation. 3O

lowing compositions are prepared by heating substantially 1 mol of monoethylin or monomethylin with 1 mol ofa dicarboxylic acid, for example, phthalic or oxalic acid, at 17 9250 C. for 3-14.- hours.

Example 1 v 'Pts. by wt. 0 Cellulose acetate 12 Monoethylin phthalate 12 Diethyl phthalate 6 Solvent"- 79 5 Example 2 Pta. by wt. Cellulose acetate 12 Monoethylin oxalate 3 Dibutyl phthalate 6 Solven 179 Application filed July 27,

The resin-like materials used in the fol-' COATING COMPOSITION 1928. Serial No. 295,858.

Ewample 3 Pts. by wt. Cellulose acetate 12 Monomethylin phthalate 3 Diethyl phthalate 6 Solvent 179 It will be apparent that a wide variety of solvents may be used in forming coating compositions of the type set forth herein, but a solvent which I have found highly satisfactory consists of acetone 17%, ethyl acetate 10%, ethyl alcohol 8%, toluene 20%, monomethyl ether of ethylene glycol 22%, acetone oil fraction boiling from 90150C. 20%, and diacetone alcohol 3%.

The above coating compositions are produced by mixing the ingredients in the proportions indicated in the ordinary way, Example 1 forming a coating composition suitable for brushing, and Examples 2 and 3 forming coating compositions suitable for spraying.

Although the examples set forth above are limited to the use of resin-like materials formed by using phthalic acid and oxalic acid, it will be understood that other organic acids containing. two or more carboxyl groups, such as tartaric acid may be substituted for phthalic acid or oxalic acid for reaction with monoethylin or monomethylin or any desired mixtures of these acids may be used for this purpose.

It will be apparent that in place of monoethylin or monomethylin Icanuse other monoalkyl ethers of glycerine, such as monopropylin and monobu tylin.

In making the resin-like materials disclosed hereinjt is sometimes desirable to vary the proportions of the ingredients and use an excess of one or the other. In such cases, if it is desired to remove the excess, this may be done in any known way, as by blowing an inert gas through the heated mass.

The process of forming resin-like materials by treating monoalkyl ethers of glycerine with organic acids containing two or more carboxyl groups is not claimed herein but is disclosed and'claimed in a co-pending application by Walter E. Lawson, Serial N 0. 295,837 filed of even date herewith.

2 v c r 1,812,385

As many apparently widely difierent embodiments of this invention may be made without departing from the spirit thereof, it is to be understood that I do not limit myself to the foregoing examples, proportions or description except as indicated in the following patent claims.

I claim:

1. A coating composition containing cellulose acetate a resinous polybasic acid ester of a monoalkyl ether of glycerine, a softener and a solvent.

2. A coating com osition containing cellulose acetate, a phtha ate of a monoalkyl ether of glycerine, a softener and a solvent.

3. A coating composition containing cellulose acetate, monoethylin phthalate, a softener and a solvent.

4. A coating composition containing 12 2o Earts b Weight of cellulose acetate, 12 parts y weig tof monoethylin phthalate, 6'parts by weight of a softener, and 79 parts by weight of a solvent. i

5. The combination of claim 4 in which the solvent contains 17% of acetone, of ethyl acetate, 8% of ethyl alcohol, 20% of toluene,

. 22% of monomethyl ether of ethylene glycol, 20% of acetone oil fraction boiling from 90 to 150 0., and 3% of diacetone alcohol.

In testimony whereof, I aflix my signature.

FREDERICK G. HAHN. 

